Project Summary Funds are requested to support eight predoctoral (Ph.D. candidates) and six postdoctoral trainees in the Training Program in Environmental Toxicology, a long-standing research training program in molecular toxicology at Vanderbilt University. This interdisciplinary program provides research career training in molecular aspects of toxicology related to environmental health. Because the field is inherently interdisciplinary, research training in the program spans chemistry, biochemistry, chemical biology, structural biology, analytical technology, microphysiological systems, functional genomics, pathogen-host interactions, disease pathology, and exposure science. The faculty preceptors have appointments in the departments of Biochemistry, Biological Sciences, Biomedical Informatics, Chemistry, Medicine, Pathology, Microbiology & Immunology, Obstetrics & Gynecology, Pediatrics and Physics all of whom have trained doctoral students and postdoctoral fellows. Training is achieved through basic and specialized coursework, research rotations, dissertation research, and participation in seminars, journal clubs, and joint research meetings. A distinctive feature of the program is hands-on training on diverse technology platforms through a highly developed and open system of research facility cores at Vanderbilt. A fraction of our graduate students are recruited through specific departments, while most matriculate through one of two umbrella programs: the Interdisciplinary Graduate Program in Biomedical and Biological Sciences (IGP) or the Quantitative and Chemical Biology Program (QCB). The students then spend their first 9 months in a common core curriculum and do laboratory rotations. Graduate students are supported for the first year by these programs or departments. Students then are recruited into the Training Program in Environmental Toxicology from these first-year pools, and training program support begins in the second year. Both predoctoral and postdoctoral trainees are selected by the Training Program Executive Committee composed of the Director, Associate Director and the Internal Advisory Committee, with guidelines to ensure distribution of trainees and monitoring of progress. The list of preceptors includes 17 faculty with diverse research interests and substantively well support research programs with the average current year direct costs available being over $1 million per investigators. Major research areas represented by our faculty preceptors include (1) Xenobiotic metabolism, detoxication, and enzymology; (2) Oxidative stress and inflammation; (3) DNA damage, genome maintenance, and replication; (4) Translational toxicology; (5) Host-pathogen-environment interactions; (6) Systems biology and developmental toxicology; and newly represented this cycle (7) Organs-on-chips and microphysiological systems. Graduates from the program have been highly successful in academia, industry, and other professional settings and include leaders in the field.